Performance
We can get a quick assessment of the performance differences between these cards by using the built-in benchmark from Thief, which spits out a simple FPS average. If you want the full-on inside-the-second performance treatment, please go read my initial GeForce GTX 980 review. By the way, our test system config for this article was the same as the one we used for that review.

You may recall that the Asus and MSI cards have the exact same base and boost clock speeds. Given that fact, there's way more drama in the performance results above than one would expect. Why is that?

To find out, I fired up a GPU monitoring utility on each card and ran MSI's Kombustor GPU burn-in tool. Here's what I saw from the two cards while they were cranking away in Kombustor:

GPU
base
clock
(MHz)

GPU
boost
clock
(MHz)

Memory
clock
(MHz)

Kombustor
GPU
voltage

Kombustor
GPU
clock
(MHz)

Asus Strix GTX 970

1114

1253

7010

1.173

1278

MSI GTX 970 Gaming 4G

1114

1253

7012

1.200

1342

Turns out the Gaming 4G supplies a little more voltage to the GM204 GPU, and as a result, it achieves higher clock speeds during normal operation. That's Nvidia's GPU Boost algorithm at work—and MSI taking advantage of it. This is not a temperature-related difference. Both cards level out at about 67°C in Kombustor, well below their defined thermal limits.

The Gaming 4G is only a few FPS faster than the Asus, so I wouldn't get too worked up over this outcome. Still, the Gaming 4G is also only a few FPS slower than a reference GTX 980. Not too shabby for the price.